I’m surprised something like this hasn’t come up yet. If I suddenly hear someone like John Updike namechecked, there’s really no central resource that I can plug his name into and get a basic bio and a list of works and reviews.
Here’s their page on Updike.
The Metacritic site has added reviews for current books to its scores for movies, music, and games. While not comprehensive, it is useful for recently published items.
And apparently there is also the Internet Book Database of Fiction
http://www.ibdof.com/
Although it’s not a reference site per se, you can find out pretty much anything about writers and books by asking at this wonderful site:
It’s relatively new so you might not have heard about it yet.
While not an all inclusive book website by any stretch of the imagination, I really enjoy browsing The Modern Word. They tend to focus on metafiction, postmodern and magical-realism types of work. And they have some really good sites dedicated to Pynchon, Joyce, Borges and others if you’re into those forms of fiction.
I also use Amazon a lot when looking for info. It contains a surprising amount of information on authors and books. Not quite what you’re looking for but it has come in handy in certain instances.
I sometimes use Bartleby, though I don’t love it with the passion that I love, say, allmusic.